1. Technical Field
The present invention relates to a liquid switch for controlling a liquid flow, and a microchip and a mass spectrometry system using thereof.
2. Background Art
In recent years, a micro-total analytical system (μ-TAS), in which chemical operations such as pre-processing, reaction, separating, detection or the like of a sample are conducted on a microchip, is rapidly developing. According to the micro-total analytical system, only a very small amount of a sample is required to be used, and analysis with higher sensitivity can be conducted with smaller environment load.
In patent literature 1, an apparatus for achieving a capillary electrophoresis by a micro channel-type chip having a configuration of being provided with a groove or a reservoir on a substrate is described. In this type of the microchip, it is critical to precisely control the timing for introducing a sample or a buffer solution into a channel in the chip. Such technique is requested not only in a separating apparatus and analysis apparatus, but also similarly in a micro chemical reactor.
Conventionally, control of the timing for introducing a sample is usually conducted by an application of an external force such as electric field, pressure and the like. However, such method is difficult to provide a precise control of a behavior of a very small amount of sample in the chip. Further, a problem of requiring larger size of the whole apparatus is also caused due to a necessity to provide an external force-applying unit.
Patent literature 1:Japanese Patent Laid-Open No. 2002-207,031